在这段代码的基础上增加能够爬取每本书评论数的代码import requests from bs4 import BeautifulSoup from threading import Thread def crawl_books(start, end): for i in range(start, end): url = 'http://search.dangdang.com/?key=%BC%C6%CB%E3%BB%FA&act=input&page_index={}'.format(i) response = requests.get(url) page = response.text soup = BeautifulSoup(page, 'lxml') books = soup.find('ul', class_='bigimg') for book in books.find_all('li'): title = book.find('a', class_='pic').get('title') author = book.find('p', class_='search_book_author').text price = book.find('p', class_='price').find('span', class_='search_now_price').text print(title, author, price) threads = [] for i in range(1, 101, 10): t = Thread(target=crawl_books, args=(i, i+10)) threads.append(t) t.start() for t in threads: t.join()

可以在循环遍历每本书的代码块中增加一个爬取评论数的代码块，具体操作如下：

1. 在循环中找到每本书的链接，例如：

book_link = book.find('a', class_='pic').get('href')

2. 访问该链接，获取评论数，例如：

response = requests.get(book_link)
page = response.text
soup = BeautifulSoup(page, 'lxml')
comment_num = soup.find('a', class_='review_num').text

3. 将评论数打印出来，例如：

print(title, author, price, comment_num)

完整代码如下：

import requests
from bs4 import BeautifulSoup
from threading import Thread

def crawl_books(start, end):
    for i in range(start, end):
        url = 'http://search.dangdang.com/?key=%BC%C6%CB%E3%BB%FA&act=input&page_index={}'.format(i)
        response = requests.get(url)
        page = response.text
        soup = BeautifulSoup(page, 'lxml')
        books = soup.find('ul', class_='bigimg')
        for book in books.find_all('li'):
            title = book.find('a', class_='pic').get('title')
            author = book.find('p', class_='search_book_author').text
            price = book.find('p', class_='price').find('span', class_='search_now_price').text
            book_link = book.find('a', class_='pic').get('href')
            response = requests.get(book_link)
            page = response.text
            soup = BeautifulSoup(page, 'lxml')
            comment_num = soup.find('a', class_='review_num').text
            print(title, author, price, comment_num)

threads = []
for i in range(1, 101, 10):
    t = Thread(target=crawl_books, args=(i, i+10))
    threads.append(t)
    t.start()

for t in threads:
    t.join()